Radiobiological Effects

The Biological Effect of Ionizing Radiation on Living Organisms

When cells are exposed to radiation it causes a change in the DNA of the cell. The radiation damage to the cell and tissue of the human body are call Radiobiologial Effect

When DNA is damaged by radiation, its coded language is also damaged resulting in cell death.

Direct Cell death may take up to days or months

Cumulative expression of carcinogenesis may take years or generations

Radiobiological Effects: Deterministic

Deterministic effects only occur once a threshold of exposure has been exceeded.

Dependent on amount of dose

Threshold level is known ie; cataracts, erythema, skin cancers, leukemia

Appropriate radiation protection methods and occupational dose limits prevent the likelihood of these effects occurring.

Extremely rare: ie; erythema, sterility, radiation sickness

Radiobiological Effects: Stochastic

Current thinking is that Stochastic Effects occur following a linear no-threshold hypothesis

No threshold for these effects, with risk occurring as dose increases ie; cancer, hereditary defects in later generations

Stochastic effects are cumulative

Occupational monitors measured in effective and cumulative dose

However, dose is negligible and impact is unknown when environmental exposure is taken into account.
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